VisB Hover enter value could be evaluated in a given state

[leuschel]

Currently the VisB hovers are static and cannot be changed depending on the current state of the B model. It would be nice to evaluate the EnterValue as a formula, just like for VisB items. This requires some non-trivial refactoring.

[leuschel]

Here is an adapted VisBHover.java file, to inherit the parsing from VisBItem, but much more needs to be done to implement this change.

package de.prob2.ui.visb.visbobjects;

import de.prob2.ui.visb.visbobjects.VisBItem;

import de.prob.animator.domainobjects.IEvalElement;
import de.prob2.ui.visb.exceptions.VisBNestedException;
import de.prob.model.classicalb.ClassicalBModel;
import de.prob.exception.ProBError;
import de.prob.statespace.Trace;
import de.prob.animator.domainobjects.EvaluationException;
import de.prob.animator.domainobjects.ClassicalB;
import de.prob2.ui.prob2fx.CurrentTrace;
import de.prob.animator.domainobjects.FormulaExpand;

/**
 * The VisBEvent is designed for the JSON / VisB file
 */
public class VisBHover extends VisBItem {

    private String hoverLeaveValue;

    /*
    from VisBItem
    private String id;
    private String attribute;
    private String value; // B Formula to compute value of attribute for SVG object id
    private Boolean optional; // if true then we ignore identifier not found errors and simply disable this item
    private IEvalElement parsedFormula; // if different from null the formula has already been parsed
    */

    public VisBHover(String hoverID, String hoverAttribute, String hoverEnterValue, String hoverLeaveValue){
        super(hoverID,hoverAttribute,hoverEnterValue,false);
        this.hoverLeaveValue = hoverLeaveValue;
    }

    public String getHoverId() {
        return getId();
    }
    public String getHoverAttr() {
        return getAttribute();
    }
    public String getHoverEnterVal() {
        return getValue();
    }
    public String getHoverLeaveVal() {
        return hoverLeaveValue;
    }

    public IEvalElement getParsedEnterFormula() {
     // getter which does not require CurrentTrace; but cannot parse on demand
        return getParsedFormula();
    }

    // a variation of getParsedValueFormula in VisBItem, but just for parsing Hover Enter formulas
    public IEvalElement getParsedEnterValueFormula(CurrentTrace currentTrace) throws VisBNestedException, ProBError {
        return getParsedValueFormula(currentTrace);
    }

    @Override
    public String toString(){
        return "";
    }
}